Rattankun Thongbun/iStock(WASHINGTON) -- Russian police announced on Tuesday they are dropping charges against the investigative journalist Ivan Golunov, an extraordinary reversal by authorities in the face of a popular outcry over his arrest on drug charges last week.

The abrupt turnaround by Russian authorities came amid mounting protests over Golunov's detention, which has been widely criticized by his supporters, including an exceptional show of solidarity by the country's journalists and even pro-Kremlin commentators.

The decision to drop the case came a day before a large protest was planned to take place in Moscow.

Golunov, a prominent reporter for the popular independent news site, Meduza, who has written on corruption and shady business practices among officials and organized crime, was arrested last Friday in Moscow. Police claimed they had found bags of the drug mephedrone on Golunov's person and during a subsequent search of his home, and charged him with intention to distribute, an offense that carries a potential 10 to 20 year prison sentence.

The case, though, quickly seemed to unravel. Golunov accused the police of planting the drugs on him and then beating him up during questioning, and police later admitted that photos they had made public, which suggested Golunov had a drug lab at his home, were misleading.

On Tuesday, authorities seemed to yield to the criticism. Interior Minister Vladimir Kolokoltsev, announced in a video statement that the case against Golunov was being closed after analysis found no sign he had committed a crime. Golunov would be released from house arrest on Tuesday, he said.

Kolokoltsev also said that he was firing the Moscow police chief who was overseeing Golunov’s case, as well as the head of the city’s narcotics division. The officers who had arrested Golunov had been suspended and would be investigated, he said.

The Investigative Committee, Russia's equivalent of the FBI, also announced it would examine the circumstances around Golunov's arrest.

It was a remarkable retreat for Russian law enforcement in the face of popular pressure. In a country where the acquittal rate in courts is less than 1%, instances of high profile cases being closed are essentially unheard of and, even in ordinary cases, charges are rarely dropped.

“I’m happy, I’m crying. We understand completely that this happened thanks to the efforts of hundreds and thousands of people. Huge gratitude to all of them,” Galina Timchenko, the general director of Meduza, told the liberal channel, TV Rain. "We all together have done the unbelievable: stopped the criminal prosecution of an innocent person."

The scale and breadth of the criticisms in support of an independent journalist have been almost unheard of in today’s Russia. The country’s three leading independent newspapers on Tuesday ran identical front pages in support of Golunov. Over two dozen state media journalists signed a letter calling for him to be freed. Celebrities, including those normally who remain outside politics, posted messages in support.

In Moscow and other cities, hundreds of protesters have taken part in demonstrations all week calling for Golunov's release.

Initially the Kremlin had suggested it favored the prosecution, pointing to the discredited photos as proof there may be grounds for the case. But as criticism mounted, there were signs that the Kremlin was changing course, and prominant pro-government anchors started to criticize the police's handling of the case.

President Vladimir Putin’s press secretary on Monday set the tone, saying that “mistakes” are sometimes made—an admission almost never heard from top Russian officials.

Most Russian observers believe the Kremlin had no direct stake in Golunov’s arrest, which most suspected had been brought about by mid-level officials or others involved in regional rackets that he most frequently wrote about. The prominent anti-corruption campaigner, Alexey Navalny on Tuesday published a report in which he claimed an FSB officer involved in a corrupt attempt to take over a funeral business had targeted Golunov for investigating it.

But the case struck a nerve in Russia as emblematic of the lawlessness and corruption in the country’s law enforcement and officials that has flourished under Putin. The case's closure was celebrated by many as evidence that Russia's civil society has the strength to force a response from authorities and as a victory over official unaccountability.

The celebration even came from inside government. On Facebook, Russia’s normally aggressive foreign ministry spokeswoman, Maria Zakharova wrote that it was “the best day” and that she was "moved to tears.”